I think a daily protein gram total of around 70 - 75 is ballpark for 1800 calories, generally. People on a low carb diet eat much more, and those on a low fat diet eat much less. You should check with your doctor or nutritionist, for an accurate assessment.

You should realize that the weight of meat does not directly translate to grams of protein. For example, beans have lots of carbohydrates in them, so their mass is made up of protein and carbohydrates. Same with meat. So, look up how much protein (usually in grams) per ounce of meat before you figure out grams of protein. I use uncooked weight, since I like to add vegetables and sauce and stuff when I cook meat. I shoot for 0.5 to 0.8 grams of protein/pound of body weight. (I have read some exercise sites on the web and that's where I got my number. It works for me. Protein makes me feel full.)

Also, I eat about 1300-1700 calories per day, and much of my protein is dairy and vegetable based.